Specifications

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Cisco Aironet 1200 Series Access Point Installation and Configuration Guide
OL-3446-01
Chapter 17 Configuring SNMP
Understanding SNMP
You must configure the SNMP agent to use the version of SNMP supported by the management station.
An agent can communicate with multiple managers; therefore, you can configure the software to support
communications with one management station using the SNMPv1 protocol and another using the
SNMPv2 protocol.
SNMP Manager Functions
The SNMP manager uses information in the MIB to perform the operations described in Table 17-1.
SNMP Agent Functions
The SNMP agent responds to SNMP manager requests as follows:
• Get a MIB variable—The SNMP agent begins this function in response to a request from the NMS.
The agent retrieves the value of the requested MIB variable and responds to the NMS with that value.
• Set a MIB variable—The SNMP agent begins this function in response to a message from the NMS.
The SNMP agent changes the value of the MIB variable to the value requested by the NMS.
The SNMP agent also sends unsolicited trap messages to notify an NMS that a significant event has
occurred on the agent. Examples of trap conditions include, but are not limited to, when a port or module
goes up or down, when spanning-tree topology changes occur, and when authentication failures occur.
SNMP Community Strings
SNMP community strings authenticate access to MIB objects and function as embedded passwords. In
order for the NMS to access the access point, the community string definitions on the NMS must match
at least one of the three community string definitions on the access point.
A community string can have one of these attributes:
• Read-only—Gives read access to authorized management stations to all objects in the MIB except
the community strings, but does not allow write access
Table 17-1 SNMP Operations
Operation Description
get-request Retrieves a value from a specific variable.
get-next-request Retrieves a value from a variable within a table.
1
1. With this operation, an SNMP manager does not need to know the exact variable name. A sequential search is performed to
find the needed variable from within a table.
get-bulk-request
2
2. The get-bulk command works only with SNMPv2.
Retrieves large blocks of data that would otherwise require the transmission of
many small blocks of data, such as multiple rows in a table.
get-response Replies to a get-request, get-next-request, and set-request sent by an NMS.
set-request Stores a value in a specific variable.
trap An unsolicited message sent by an SNMP agent to an SNMP manager when some
event has occurred.